drupal/core/modules/system/templates/menu-local-tasks.html.twig

{#
/**
 * @file
 * Default theme implementation to display primary and secondary local tasks.
 *
 * Available variables:
 * - primary: HTML list items representing primary tasks.
 * - secondary: HTML list items representing secondary tasks.
 *
 * Each item in these variables (primary and secondary) can be individually
 * themed in menu-local-task.html.twig.
 *
 * @ingroup themeable
 */
#}
{% if primary %}
  <h2 class="visually-hidden">{{ 'Primary tabs'|t }}</h2>
  <ul>{{ primary }}</ul>
{% endif %}
{% if secondary %}
  <h2 class="visually-hidden">{{ 'Secondary tabs'|t }}</h2>
  <ul>{{ secondary }}</ul>
{% endif %}